Circuit breaker



.Feb. 26 1924. 1,484,645

I, c. F. HOLMES CIRCUIT BREAKER Filed April 15. 1922 WWW Patented Feb. 26, 1924.

UNITED STATES CHARLES F. HOLMES, OF CHICAGO, ILLINOIS.

CIRCUIT BREAKER.

Application filed April 15, 1922. Serial No. 552,964.

To all whom it may concern:

Be it known that I, CHARLES F. HOLMES, a citizen of the United States, and a resident of the city of Chicago, county of Cook, and State of Illinois, have invented certain new and useful Improvements in Circuit Breakers, of which the following is a specification.

My invention relates to circuit breakers and more particularly to circuit breakers adapted to take the place of safety fuses as ordinarily used to break a circuit when same becomes overloaded.

Another object of the invention is to utilize an electromagnet which is adapted to become sufiiciently energized by various degrees of overload on the circuit to attract an armature and thereby actuate means for breaking the circuit.

Other objects will appear hereinafter.

The invention consists in the combinations and arrangements of the parts hereinafter described and claimed.

The invention will be best understood by reference to the accompanying drawings forming a part of this specification, and in which,

Fig. 1 is a top plan view of the invention showing the circuit breaking means in inoperative position in full lines and operative position in dotted lines,

Fig. 2 is a sectiohal view on the line 2-2 of Fig. 1, also diagrammatically showing the circuit breaker in series with a lamp circuit,

Fig. 3 is a detailed view of trigger mechanism which actuates the circuit breaker,

Fi 4 is a detailed View of a gravity adjusta 1e armature used in connection with the invention, and

Fig. 5 is a fragmentary view of the circuit reaking means showing contact members mounted thereon.

Referring to the drawings, 1 represents a plug adapted to be screwed into a socket (not shown) provided in a cut-out block in the ordinary manner. The plug 1 is preferably secured to a yoke 2 of soft iron or other magnetic material, such yoke preferably being provided with a depend ing core 3, having a square bore 4 extending therethrough, and having a coil of wire disposed thereabout to form a magnet.

The lower end of the core 3 is preferably rovided with a pair of spaced annular anges 5, between which is slidably mounted the ring portion 6 of an armature 7.

The armature 7 is provided with a weighted portion 8, and disposed beneath the armature 7 is a suitable stop 9 adapted to limit the movement of the armature 7. By reason of the weighted portion 8 the armature 7 will always remain in depending operative position despite rotation of the device when screwing same into a socket.

Slidably mounted in the bore 4 is a plunger 10, one end of which is adapted to be engaged by the armature 7 to impart operative movement thereto, the opposite end of said plunger being square and provided adjacent its end with an annular groove 11 for a purpose as will presently appear.

Preferably slidably but non-rotatably mounted on the square end of the plunger 10 adjacent the groove 11, is a substantially U shaped bridge member 12. A spring 13 is preferably disposed about the end of the plunger 10, the opposite end of said spring being secured to a pin 14 on the bridge member 12. The legs of the bridge member 12 each preferably carries a pair of resilient contact members 15 and 16, adapted in operative position to engage contacts 17 and 17 mounted in suitable position on opposite sides of the yoke 2. Each contact 15- preferably comprises a carbon block removably held in position by any suitable means, the purpose of this construction being to prevent the device being rendered inoperative by an unusual overload of current entering the circuit, and burning out the contacts.

As clearly shown in Fig. 2, the device is connected in series with a lamp circuit, the lead 18 being shown entering the magnet at 19, emerging therefrom at 20, and being secured to the contact 17 The lead 19 is connected to the plug and leads to the contact 17.

In normal position the contacts 15 and 16 on the bridge 12 are held in engagement with the contacts 17 and 17, the bridge in turn being held in operative position by engagement of the square aperture in the bridge 12 with the square end of the plunger 10. In this position, with a normal amount of current passing through the circuit, the magnet is so slightly energized that it does not attract the armature 7; however, when an excessive amount of current passes through the circuit the magnet is sufiiciently energized to attract its armature 7 which moves the plunger 10 so as to bring the groove 11 in engagement with the square aperture in the bridge 12, the bridge 12 then being free to be swung to inoperative position by action of the spring 13 thereon, thus breaking the circuit. In order to again set the dev'ce it is only necessary to rotate the bridge 12 to operative position to engage the square end of the plunger 10 with the square aperture in the bridge 12. Thus it will be seen that while serving in the same manner as a safety fuse, the device can be reset an indefinite number of times, and is practically indestructible. In addition the device could be constructed and tested to operate at accurately predetermined amounts of oven load, which is practically impossible with safety plugs of fusible mater'al.

lVhile I have illustrated and described the preferred f rm of construction for carrying my invention into effect, this is ca a sle of variation and modification without departing from the spirit of the invention. 1, therefore, do not wish to be limited to the precise details of the construction set forth, but desire to avail myself of sucl variations and modifications as come within the scope of the appendeo. claims.

Having described my invention, what I claim as new and desire to secure by Letters Patent, is:

1. A device of the character described comprising a magnetic core ha *ing a square bore; a square plunger slidably mounted in said bore and having an annular groove formed about one end; a circuit breaking member ha ing a square aperture adapted to slidably engage the square end of said plunger to retain same in operative position; aspring connected to said member and said end, and normally urging said member to inoperative position; and an armature adapted to be attracted by said in gnetic core for imparting an operative stroke to said plunger to cause said aperture to engage said groove to release said member.

2. A device of the charact r described comprising a horizontally dispo. rotatable magnetic core; an armature having a ring portion loosely held on said core; and a weighted portion on said armature for retaining same in position despite rotation of said core.

3. A device of the character described comprising a hollow magnetic core having a plunger slidably mounted therein; a circuit breaking member mounted on said plunger and having means to swing it on said plunger to inoperative position; trigger mechanism connecting said circuit breaking member to said plunger; and an armature slidably mounted on said core and adapted to engage said plunger to actuate said trigger mechanism to release said circuit breaking member.

4-. A device of the character described comprising a yoke; a hollow magnetic core mounted centrally on said yoke; contacts mounted on opposite sides of said yoke; 11 plunger slidably n'iounted in said core; a circuit breaking member normally engaging said contacts; trigger mechanism connecting said plunger and said circuit breaking member; and an armature adapted to engage said plunger to actuate said trigger mechanism to release said circuit breaking member.

5. A device of the character described comprising a yoke; contacts mounted on opposite sides of said yoke; a magnetic core mounted centrally on said yoke and having a square bore therein: a square plunger slidably mounted in said bore and having an an nular groove formed about its end; a circuit breaking member having a square aperture adapted to slidably engage the square end of said plunger to retain the same in operative position; means normally urging said member to inoperative position; and an armature adapted to be operated by said magnetic core for imparting an operative stroke to said plunger to cause said aperture to engage said groove to release said member.

6. A device of the character described comprising a yoke having a magnetic core mounted thereon; contacts mounted at opposite sides of said yoke; a U-shaped member rotatably mounted upon said yoke; trigger mechanism for holding the legs of said member in engagement with said contacts; and an armature for actuating said trigger mechanism to release said member.

7. A device of the character described comprising a yoke having a magnetic core mounted thereon; contacts mounted at opposite sides of said yoke; a U-shaped member rotatably mounted upon said yoke; resilient contact fingers mounted upon the legs of said U-shaped member and adapted to en gage said contacts; trigger mechanism for holding said U-shapcd member in engagement with said contacts; and an armature adapted to be operated by said magnetic core for actuating said trigger mechanism to release said U-shaped member.

In testimony whereof I have signed my name to this specification in the presence of two subscribing witnesses.

CHARLES F. HOLMES.

Witnesses FREDA C. APPLETON, h'lnaeann'r Arum. 

